Treatment of Drug-Resistant Tuberculosis. An Official ATS/CDC/ERS/IDSA Clinical Practice Guideline

Functionalized Polydopamine Nanoparticles: A Promising Drug Delivery Platform for the Treatment of Tuberculosis

Tuberculosis (TB) is considered a major infectious disease by the World Health Organization. The WHO estimates that there are 1.8 million TB deaths, and 10.4 million new cases of the disease reported yearly. While there are conventional therapies for TB, they have drawbacks such as a lengthy pill regimen, rigorous scheduling, and protracted treatment duration, which can result in strains of the disease that are multidrug-resistant (MDR) and extensively drug-resistant (XDR). Future TB control is at risk due to the emergence of MDR strains. This worry has made the hunt for a successful remedy necessary. One biomedical innovation has been the application of nanotechnology, which offers a fresh avenue of treating TB. Such nanotechnology approach includes Polydopamine (PDA) nanoparticles which have demonstrated the ability to reduce these difficulties. In recent times, PDA, which is an intriguing bioinspired polymer, has become a material of choice for designing drug delivery nano-systems. In fact, PDA nanoparticles show several intriguing characteristics, such as easy manufacturing approach, biocompatibility, the ability to scavenge free radicals, and photothermal and photoacoustic features. It is easily functionalized to promote blood circulation, cellular absorption, and drug release, among other functions. As a result, this review has examined the various PDA functionalization techniques aimed at overcoming MDR and enhancing TB treatment.

Ivacaftor affects the susceptibility of standard-of-care drugs used to treat Mycobacterium abscessus lung disease

Patients with cystic fibrosis have dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR), and this predisposes them to nontuberculous mycobacteria (NTM), including Mycobacterium abscessus (MAB), infection. We found that one of the CFTR modulators, ivacaftor, kills MAB in a concentration-dependent manner, with killing efficacy comparable to amikacin and imipenem, drugs in guideline-based regimens. Using clinical isolates of MAB, amikacin 1/4× MIC concentration combined with ivacaftor killed 2.67 log10 CFU/mL MAB.

Synthesis, Antimycobacterial Activity, and Computational Insight of Novel 1,4-Benzoxazin-2-one Derivatives as Promising Candidates against Multidrug-Resistant Mycobacterium Tuberculosis

In the search for new antitubercular agents, a series of 1,4-benzoxazinone-based compounds is designed, synthesized, and evaluated. These molecules show potent antimycobacterial activity, with a minimum inhibitory concentration between 2 and 8 μg mL-1. This interesting profile includes activity against several drug-resistant strains and minimal cytotoxicity against mammalian Vero cells. Structural similarities with analogs from the literature are reinforced by molecular docking and molecular dynamics simulations, suggesting that inhibition of the menaquinone-B enzyme as a potential mechanism of action. In addition, the active compounds exhibit favorable predicted Absorption, Distribuition, Metabolism, and Excretion (ADME) properties, indicating their potential for oral administration in humans.

Adverse events of tuberculosis preventive therapy among individuals with latent tuberculosis infection: A nationwide cohort study in South Korea

OBJECTIVES

This study assessed adverse event with tuberculosis preventive therapy (TPT) regimens among individuals with latent tuberculosis infection (LTBI).

METHODS

Using national health insurance data, we analyzed individuals newly diagnosed with LTBI between 2015 and 2020. The TPT group, prescribed 3 months of isoniazid and rifampicin (3HR), 4 months of rifampicin (4R), or 9 months of isoniazid (9H), was matched with a control group through 1:1 propensity score matching. Drug-related adverse events were reported.

RESULTS

Of 220,483 diagnosed with LTBI, 49.0% received TPT, primarily 3HR (74.6%). The incidence of any adverse events with TPT was 11.90%, with 8.94% of these events being severe events requiring hospitalization. Hepatotoxicity risk was 6.48-, 4.79-, and 3.50-fold with 3HR, 9H, and 4R, respectively, compared to controls. Severe cutaneous adverse reaction risk was 4.27-, 1.83-, and 1.93-fold with 3HR, 9H, and 4R. 4R had the lowest risk of any adverse events, while 3HR had the highest. Permanent discontinuation occurred in 2.3%, 3.1%, and 3.3% with 4R, 9H, and 3HR, respectively. Unlike 9H, rifampicin-based regimens showed no age-related trend in adverse event risk.

CONCLUSIONS

4R is a better option considering safety across a broad age range, suggesting it could be encouraged in the LTBI population.

Time to sputum culture conversion as a predictor of cure in multidrug-resistant tuberculosis patients: a multicenter retrospective cohort study in Pakistan

This study aimed to evaluate how the time to sputum culture conversion (SCC) predicts cure and to identify factors associated with delayed SCC and cure among multidrug-resistant tuberculosis (MDR-TB) patients receiving longer treatment regimens of 18-24 months. This multicenter retrospective cohort study was conducted at eight programmatic management units. A total of 462 patients with confirmed pulmonary MDR-TB were enrolled at eight PMDT sites between January 2017 and August 2018 with available treatment outcomes till 30th June, 2020. Survival analysis was done using the Kaplan-Meier curve, and Cox proportional hazards model and binary logistic regression were performed to determine factors associated with time to SCC and cure. Statistical significance was set at p<0.05. A total of 424/462 (91.8%) patients achieved SCC, with a cure rate of 75.5%. The mean time to SCC was 2.4 months (interquartile range = 1-3 months). Factors such as employment [hazard ratio (HR)=0.654, p=0.001], sputum smear grading score +2+3 (HR = 0.638, p=0.014), resistance to first-line drugs HREZ (HR=0.716, p=0.014), and resistance to second-line drugs, fluoroquinolones (HR=0.698, p≤0.001) were significantly associated with SCC. In the current study, the cure rate was 75.5% (349/462). In the binary logistic regression, month 1 [odds ratio (OR)=2.601, p≤0.001), month 2 (OR=3.14, p≤0.001), month 3 (OR=5.219, p≤0.001), month 4 (OR=6.788, p≤0.001), month 5 (OR=21.512, p≤0.001), and month 6 (OR=31.806, p≤0.001) had a statistically significant association with cure. In predicting cure, the overall sensitivities of SCC at 1, 2, 3, 4, 5, and 6 months were 37.2%, 64.1%, 85.9%, 91.1%, 97.4%, and 98.2%, respectively, and the specificities were 81.4%, 63.7%, 46.0%, 39.8%, 36.2%, and 35.3%, respectively. Interestingly, the combined sensitivity and specificity of SCC at 3 and 4 months in predicting cure were similar to those observed at 5 and 6 months.

Limitations of the MTB/RIF Assay: An Xpert Review of 4 Clinical Cases

Current U.S. Centers for Disease Control and Prevention tuberculosis (TB) guidelines recommend molecular testing for initial diagnosis of TB and detection of rifampin resistance to expedite initiation of proper treatment. The Cepheid Xpert MTB/RIF assay can detect members of the Mycobacterium tuberculosis complex and rifampin resistance by evaluating for mutations in the rpoB gene. However, false-positive and false-negative detection of M tuberculosis and rifampin resistance results can lead to incorrect treatment of patients, including overuse of second-line anti-TB drugs, and may result in patient harm and increased healthcare cost. We present a series of 4 cases to demonstrate the limitations of the Xpert MTB/RIF assay in the diagnosis of TB, emphasizing the importance of follow-up confirmatory testing and laboratory oversight in reporting accurate results.

Innovative Strategies for Combating Multidrug-Resistant Tuberculosis: Advances in Drug Delivery Systems and Treatment

Multidrug-resistant tuberculosis (MDR-TB) is a significant public health challenge globally, exacerbated by the limited efficacy of existing therapeutic approaches, prolonged treatment duration, and severe side effects. As drug resistance continues to emerge, innovative drug delivery systems and treatment strategies are critical to combating this crisis. This review highlights the molecular mechanisms underlying resistance to drugs in Mycobacterium tuberculosis, such as genetic mutation, efflux pump activity, and biofilm formation, contributing to the persistence and difficulty in eradicating MDR-TB. Current treatment options, including second-line drugs, offer limited effectiveness, prompting the need for innovation of advanced therapies and drug delivery systems. The progression in drug discovery has resulted in the approval of innovative therapeutics, including bedaquiline and delamanid, amongst other promising candidates under investigation. However, overcoming the limitations of traditional drug delivery remains a significant challenge. Nanotechnology has emerged as a promising solution, with nanoparticle-based drug delivery systems offering improved bioavailability and targeted and controlled release delivery, particularly for pulmonary targeting and intracellular delivery to macrophages. Furthermore, the development of inhalable formulations and the potential of nanomedicines to bypass drug resistance mechanisms presents a novel approach to enhancing drug efficacy. Moreover, adjunctive therapies, including immune modulation and host-directed therapies, are being explored to improve treatment outcomes. Immunotherapies, such as cytokine modulation and novel TB vaccines, offer complementary strategies to the use of antibiotics in combating MDR-TB. Personalized medicine approaches, leveraging genomic profiling of both the pathogen and the host, offer promise in optimizing treatment regimens and minimizing drug resistance. This review underscores the importance of multidisciplinary approaches, combining drug discovery, advanced delivery system development, and immune modulation to address the complexities of treating MDR-TB. Continued innovation, global collaboration, and improved diagnostics are essential to developing practical, accessible, and affordable treatments for MDR-TB.

Whole-Genome Sequencing of Linezolid-Resistant and Linezolid-Intermediate-Susceptibility Enterococcus faecalis Clinical Isolates in a Mexican Tertiary Care University Hospital

Linezolid-non-susceptible Enterococcus faecalis (LNSEf) has emerged as a critical clinical concern worldwide, yet data from Latin American settings remain scarce. This study aimed to investigate the molecular epidemiology and mechanisms underlying LNSEf in a Mexican tertiary care university hospital, focusing on clinical correlates and clonal relationships. A total of 392 non-duplicated E. faecalis isolates were collected over 12 months, of which 24 with minimum inhibitory concentrations ≥4 µg/mL underwent whole-genome sequencing to identify specific resistance determinants (optrA, cfrA, 23S rRNA mutations) and to perform multilocus sequence typing (MLST) and phylogenetic analyses. Of the 392 isolates, 6.12% showed linezolid non-susceptibility, predominantly linked to plasmid- or chromosomally encoded optrA; only two isolates carried cfrA. No mutations were detected in 23S rRNA domain V or ribosomal proteins L3/L4. Clinically, LNSEf strains were associated with immunosuppression, previous surgical interventions, and prolonged hospital stays. Although most LNSEf isolates retained susceptibility to ampicillin, vancomycin, and daptomycin, they exhibited high rates of resistance to other antibiotic classes, particularly aminoglycosides and fluoroquinolones. These findings underscore the emergence of LNSEf in this region, highlighting the need for robust genomic surveillance, strict infection control, and judicious antimicrobial stewardship to curb further dissemination.

Evaluation of treatment outcomes and associated risk factors in children with TB in Bangladesh

BACKGROUND

Children aged 0-14 years old make up 4% of the total number of people diagnosed with TB in Bangladesh. Local pediatric treatment outcomes and associated factors are poorly understood; further understanding can inform tailored interventions to close delivery gaps.

METHODS

To assess the risk factors for unsuccessful treatment outcomes among children receiving TB treatment in 119 health facilities in Mymensingh Division, we conducted systematic verbal screening from 2018 to 2021. Unsuccessful outcomes, including death, treatment failure, or loss to follow-up (LTFU), were analysed using log-binomial regression to examine the association with demographic and clinical characteristics.

RESULTS

Among 1,967 children with reported outcomes, 99.3% (n = 1,954) were successful. The primary reason for unsuccessful treatment was LTFU (n = 12, 0.6%), followed by treatment failure (n = 1, 0.1%). After controlling for age and sex, children with fever had a reduced risk of unsuccessful outcomes compared to those without fever (RR 0.23, 95% CI 0.06-0.82).

CONCLUSION

Most children with TB were successfully treated. LTFU was the leading reason for unsuccessful treatment outcomes in this cohort. Children with fever were less likely to have unsuccessful treatment outcomes, possibly because they were more intensely engaged in care than children without fever due to their presentation of symptoms. Continued research on pediatric TB presentation and treatment outcomes is essential for developing targeted strategies for early detection and treatment support.

Revolutionizing tuberculosis treatment: Breakthroughs, challenges, and hope on the horizon

Tuberculosis (TB), an infectious disease caused by the bacterium Mycobacterium tuberculosis (Mtb), was responsible for the deaths of approximately 1.3 million people in 2022. In addition, 7.5 million new cases of TB have been reported. Present-day treatments require a daily dosing of a multiple-drug regimen for a minimum of six-month, but poor adherence and other factors often lead to treatment failure. Consequently, drug-resistant TB strains have become a growing concern, leading to more complex and expensive treatments. Promising drugs such as bedaquiline, delamanid, and pretomanid have been recently released, and 19 drug candidates are currently at different phases of clinical trials, addressing the problem of drug-resistant TB. Notwithstanding recent advances, the development of effective and safe drugs with novel mechanisms of action remains a challenge due to the unique nature of Mtb. Despite the persistent need for new treatments, TB research remains underfunded, highlighting the importance of collaborations between academia and the private sector in the advancement of anti-TB drug development. This review provides a perspective on the dynamic landscape of anti-TB drug discovery in recent years, offering hope for a more effective approach to combat this persistent global health threat.

Discovery of potent dihydro-oxazinoquinolinone inhibitors of GuaB for the treatment of tuberculosis

Tuberculosis is the leading cause of death from an infectious disease, and is caused by Mycobacterium tuberculosis (M.tb). More than 1 billion people worldwide are thought to harbor an M.tb infection. The multidrug therapy that represents the current standard of care requires a minimum of four months of dosing and drug resistant Mycobacterium tuberculosis treatment regimens are significantly longer. Inosine-5'-monophosphate dehydrogenase (GuaB) is the enzyme that performs the rate-limiting step in de novo guanine nucleotide biosynthesis that is critical for growth and viability of bacteria including M.tb. The development of a novel antibiotic that inhibits GuaB could combine with existing therapies in novel ways and thereby contribute to effective therapeutic regimens for the treatment of tuberculosis. Here we describe the discovery of structurally distinct small molecule GuaB inhibitors that are potent against M.tb H37Ra and H37Rv strains and have desirable safety and ADME profiles.

Exposure to Rifampicin and its Metabolite 25-Deacetylrifampicin Rapidly Decreases During Tuberculosis Therapy

BACKGROUND AND OBJECTIVE

Limited information is available on the pharmacokinetics of rifampicin (RIF) along with that of its active metabolite, 25-deacetylrifampicin (25-dRIF). This study aimed to analyse the pharmacokinetic data of RIF and 25-dRIF collected in adult patients treated for tuberculosis.

METHODS

In adult patients receiving 10 mg/kg of RIF as part of a standard regimen for drug-susceptible pulmonary tuberculosis enrolled in the Opti-4TB study, plasma RIF and 25-dRIF concentrations were measured at various occasions. The RIF and 25-dRIF concentrations were modelled simultaneously by using a population approach. The area under the concentration-time curves of RIF and 25-dRIF were estimated on each occasion of therapeutic drug monitoring. Optimal RIF exposure, defined as an area under the concentration-time curve over 24 hours/minimum inhibitory concentration > 435, was assessed.

RESULTS

Concentration data (247 and 243 concentrations of RIF and 25-dRIF, respectively) were obtained in 35 patients with tuberculosis (10 women, 25 men). Mycobacterium tuberculosis minimum inhibitory concentration ranged from 0.06 to 0.5 mg/L (median = 0.25 mg/L). The final model was a two-compartment model including RIF metabolism into 25-dRIF and auto-induction. Exposure to 25-dRIF was low, with a mean area under the concentration-time curve over 24 h ratio of 25-dRIF/RIF of 14 ± 6%. The area under the concentration-time curve over 24 h of RIF and 25-dRIF rapidly decreased during therapy, with an auto-induction half-life of 1.6 days. Optimal RIF exposure was achieved in only six (19.3%) out of 31 patients upon first therapeutic drug monitoring.

CONCLUSIONS

Exposure to both RIF and 25-dRIF rapidly decreased during tuberculosis therapy. The contribution of 25-dRIF to overall drug exposure was low. Attainment of the target area under the concentration-time curve over 24 hours/minimum inhibitory concentration for RIF was poor, supporting an increased RIF dosage as an option to compensate for auto-induction.

Advancing against drug-resistant tuberculosis: an extensive review, novel strategies and patent landscape

Drug-resistant tuberculosis (DR-TB) represents a pressing global health issue, leading to heightened morbidity and mortality. Despite extensive research efforts, the escalation of DR-TB cases underscores the urgent need for enhanced prevention, diagnosis, and treatment strategies. This review delves deep into the molecular and genetic origins of different types of DR-TB, highlighting recent breakthroughs in detection and diagnosis, including Rapid Diagnostic Tests like Xpert Ultra, Whole Genome Sequencing, and AI-based tools along with latest viewpoints on diagnosis and treatment of DR-TB utilizing newer and repurposed drug molecules. Special emphasis is given to the pivotal role of novel drugs and discusses updated treatment regimens endorsed by governing bodies, alongside innovative personalized drug-delivery systems such as nano-carriers, along with an analysis of relevant patents in this area. All the compiled information highlights the inherent challenges of current DR-TB treatments, discussing their complexity, potential side effects, and the socioeconomic strain they impose, particularly in under-resourced regions, emphasizing the cost-effective and accessible solutions. By offering insights, this review aims to serve as a compass for researchers, healthcare practitioners, and policymakers, emphasizing the critical need for ongoing R&D to improve treatments and broaden access to crucial TB interventions.

Clinical Pharmacokinetics of Antitubercular Drugs in the Overweight and Obese Population: Implications for Dosage Adjustments

The rise in global obesity prevalence has increased the need to understand the pharmacokinetics of drugs in overweight and obese individuals. Tuberculosis remains a significant health challenge, and its treatment outcomes can be influenced by the pharmacokinetic profiles of antitubercular agents. This literature review aims to point out the clinical pharmacokinetics of antitubercular drugs in the overweight and obese patient population, highlighting considerations for potential dosage adjustments. We conducted a comprehensive search of the PubMed US National Library of Medicine from inception to January 2024. Articles focusing on the pharmacokinetics of antitubercular agents used for both drug-susceptible and multidrug-resistant tuberculosis in overweight and obese adults were included. In total, 349 scientific articles were identified and examined for human pharmacokinetic parameters. Of these, 19 were included in this article. To highlight potential differences, pharmacokinetic data for normal-weight tuberculosis patients are also presented, albeit selectively. In general, pharmacokinetic studies of antitubercular agents in overweight and obese individuals are lacking. Fixed-dose combinations often used in the treatment of drug-susceptible tuberculosis are not recommended when treating these population groups. Rather, individual dosing based on therapeutic drug monitoring and the known solubility of the substance should be considered. To improve the management of tuberculosis in overweight and obese patients, there is an urgent need for pharmacokinetic studies and, ultimately, adequate dosing in this patient population, especially given the increasing prevalence of obesity.

Oral Regimens for Rifampin-Resistant, Fluoroquinolone-Susceptible Tuberculosis

BACKGROUND

For decades, poor treatment options and low-quality evidence plagued care for patients with rifampin-resistant tuberculosis. The advent of new drugs to treat tuberculosis and enhanced funding now permit randomized, controlled trials of shortened-duration, all-oral treatments for rifampin-resistant tuberculosis.

METHODS

We conducted a phase 3, multinational, open-label, randomized, controlled noninferiority trial to compare standard therapy for treatment of fluoroquinolone-susceptible, rifampin-resistant tuberculosis with five 9-month oral regimens that included various combinations of bedaquiline (B), delamanid (D), linezolid (L), levofloxacin (Lfx) or moxifloxacin (M), clofazimine (C), and pyrazinamide (Z). Participants were randomly assigned (with the use of Bayesian response-adaptive randomization) to receive one of five combinations or standard therapy. The primary end point was a favorable outcome at week 73, defined by two negative sputum culture results or favorable bacteriologic, clinical, and radiologic evolution. The noninferiority margin was -12 percentage points.

RESULTS

Among the 754 participants who underwent randomization, 699 were included in the modified intention-to-treat analysis, and 562 in the per-protocol analysis. In the modified intention-to-treat analysis, 80.7% of the patients in the standard-therapy group had favorable outcomes. The risk difference between standard therapy and each of the four new regimens that were found to be noninferior in the modified intention-to-treat population was as follows: BCLLfxZ, 9.8 percentage points (95% confidence interval [CI], 0.9 to 18.7); BLMZ, 8.3 percentage points (95% CI, -0.8 to 17.4); BDLLfxZ, 4.6 percentage points (95% CI, -4.9 to 14.1); and DCMZ, 2.5 percentage points (95% CI, -7.5 to 12.5). Differences were similar in the per-protocol population, with the exception of DCMZ, which was not noninferior in that population. The proportion of participants with grade 3 or higher adverse events was similar across the regimens. Grade 3 or higher hepatotoxic events occurred in 11.7% of participants overall and in 7.1% of those receiving standard therapy.

CONCLUSIONS

Consistent results across all the analyses support the noninferior efficacy of three all-oral shortened regimens for the treatment of rifampin-resistant tuberculosis. (Funded by Unitaid and others; endTB ClinicalTrials.gov number, NCT02754765.).

Additive Effects of Glutathione in Improving Antibiotic Efficacy in HIV-M.tb Co-Infection in the Central Nervous System: A Systematic Review

BACKGROUND

HIV and tuberculosis (TB) co-infection poses a significant health challenge, particularly when involving the central nervous system (CNS), where it leads to severe morbidity and mortality. Current treatments face challenges such as drug resistance, immune reconstitution inflammatory syndrome (IRIS), and persistent inflammation. Glutathione (GSH) has the therapeutic potential to enhance treatment outcomes by improving antibiotic efficacy, reducing inflammation, and mitigating immune dysfunction.

METHODS

Relevant studies were identified through systematic searches of PubMed, Elsevier, WHO, and related databases. Inclusion criteria focused on preclinical and clinical research examining GSH or its precursors in HIV, TB, or co-infection, with emphasis on microbial control, immune modulation, and CNS-related outcomes.

RESULTS

Preclinical studies showed that GSH improves macrophage antimicrobial function, reduces oxidative stress, and limits Mycobacterium tuberculosis (M.tb) growth. Animal models demonstrated reduced bacterial burden in the lungs, liver, and spleen with GSH supplementation, along with enhanced granuloma stability. Clinical studies highlighted increased TH1 cytokine production, reduced inflammatory markers, and improved CD4+ T cell counts in HIV-M.tb co-infected patients. N-acetylcysteine (NAC), a GSH precursor, was shown to significantly enhance the efficacy of first-line TB antibiotics and mitigate treatment-associated toxicity.

DISCUSSION

GSH shows promise as an adjunct therapy for HIV-M.tb co-infection, particularly for cases involving the CNS, where it may improve immune recovery and reduce inflammation. However, evidence is limited by small sample sizes and a lack of randomized trials. Future research should focus on developing CNS-directed GSH formulations and evaluating its integration into current treatment protocols to address the dual burden of HIV and TB, ultimately improving patient outcomes.

Saliva-based point-of-care assay to measure the concentration of pyrazinamide using a mobile UV spectrophotometer

INTRODUCTION

Pyrazinamide, one of the first-line antituberculosis drugs, displays variability in drug exposure that is associated with treatment response. A simple, low-cost assay may be helpful to optimize treatment. This study aimed to develop and validate a point-of-care assay to quantify the concentration of pyrazinamide in saliva.

METHODS

All measurements were conducted using the nano-volume drop function on the mobile ultraviolet (UV) spectrophotometer (NP80, Implen, Germany). Assay development involved applying second derivative spectroscopy in combination with the Savitzky-Golay filter between wavelengths of 200-300 nm to increase spectral resolution. Assay validation included assessing selectivity, linearity, accuracy, precision, carry-over and matrix effects. Specificity was also analysed by evaluating the impact of co-administered medications on pyrazinamide results. Sample stability was measured at various temperatures up to 40°C.

RESULTS

The calibration curve (7.5-200 mg/L) was linear (R2 = 0.9991). The overall accuracy (bias%) and precision (CV%) ranged from -0.66% to 5.15%, and 0.56% to 4.95%, respectively. Carry-over and matrix effects were both acceptable with a bias% of <±4% and CV% of <7.5%. Commonly co-administered medications displayed negligible interferences. Levofloxacin displayed analytical interference (bias% = -10.21%) at pyrazinamide concentrations < 25 mg/L, but this will have little clinical implications. Pyrazinamide was considered stable in saliva after 7 days in all storage conditions with a CV% of <6.5% and bias% of <±10.5% for both low- and high-quality control concentrations.

CONCLUSIONS

A saliva-based assay for pyrazinamide has been successfully developed and validated using the mobile UV spectrophotometer.

Evaluation of a Commercial Multiplex Real-Time PCR with Melting Curve Analysis for the Detection of Mycobacterium tuberculosis Complex and Five Nontuberculous Mycobacterial Species

BACKGROUND

Accurate and timely diagnosis of mycobacterial infections, including Mycobacterium tuberculosis complex (MTBC) and nontuberculous mycobacteria (NTM), is crucial for effective disease management.

METHODS

This study evaluated the performance of the NeoPlex TB/NTM-5 Detection Kit (NeoPlex assay, Seongnam, Republic of Korea), a multiplex real-time PCR assay that incorporates melting curve analysis, compared with the line-probe assay (LPA). The NeoPlex assay could simultaneously detect and differentiate MTBC from five other NTM species: Mycobacterium intracellulare, Mycobacterium avium, Mycobacterium kansasii, Mycobacterium abscessus, and Mycobacterium massiliense. A total of 91 acid-fast bacillus culture-positive samples, comprising 36 MTBC and 55 NTM isolates, were collected from the Korea University Anam Hospital.

RESULTS

The NeoPlex assay successfully detected nucleic acids in 87 of the 91 isolates (95.6%). Notably, it identified additional mycobacterial nucleic acids not detected by the LPA in eight isolates. These findings were confirmed via DNA sequencing. The assay had 100% sensitivity and specificity for M. intracellulare, M. abscessus, M. massilense, NTM, and MTBC, whereas it had 100% specificity and sensitivity of 90.9% and 75.0% for M. avium and M. kansasii, respectively.

CONCLUSIONS

These results highlight the potential of the NeoPlex assay to enhance rapid and accurate diagnosis of mycobacterial infections, particularly in settings in which prompt treatment initiation is essential.

Epidemiology of Latent Tuberculosis in Rheumatic Immune-Mediated Inflammatory Diseases-Study of 1117 Patients and Descriptive Literature Review

Background/Objectives: Patients with rheumatic immune-mediated diseases (rheumatic-IMID) and latent tuberculosis (LTBI) are at an increased risk of developing active tuberculosis (TB); therefore, screening is recommended before starting biological treatment. The aims of this study were as follows: (i) to assess the prevalence of LTBI, (ii) to determine the importance of using a booster test in TST-negative patients, (iii) to compare the tuberculin skin test (TST) with the interferon-gamma release assay (IGRA), (iv) to perform a review of the prevalence of LTBI. Methods: A cross-sectional hospital study was performed, including patients diagnosed with rheumatic-IMID who underwent a TST and/or IGRA during the period 2016-2020. If the first TST was negative, a new TST (booster) was performed. Results: A total of 1117 patients were included. The overall prevalence of LTBI was estimated to be 31.7% (95% confidence interval, 29.74-33.66). The LTBI prevalence ranged from 38.5% for vasculitis to 14% for sarcoidosis. The booster test was positive in 22.9% of 817 patients with a negative or indeterminate IGRA. The IGRA was positive in 3.8% of 793 patients with a negative booster.The adjusted Cohen's kappa coefficient between TST (+booster) and IGRA was 0.62. Conclusions: LTBI is frequent in patients with rheumatic-IMID. IGRA and TST (+booster) show a moderate, fair grade of agreement. Therefore, performing both tests before biological therapy should be highly recommended.

State of the art of real-life concentration monitoring of rifampicin and its implementation contextualized in resource-limited settings: the Tanzanian case

The unique medical and socio-economic situation in each country affected by TB creates different epidemiological contexts, thus providing exploitable loopholes for the spread of the disease. Country-specific factors such as comorbidities, health insurance, social stigma or the rigidity of the health system complicate the management of TB and the overall outcome of each patient. First-line TB drugs are administered in a standardized manner, regardless of patient characteristics other than weight. This approach does not consider patient-specific conditions such as HIV infection, diabetes mellitus and malnutrition, which can affect the pharmacokinetics of TB drugs, their overall exposure and response to treatment. Therefore, the 'one-size-fits-all' approach is suboptimal for dealing with the underlying inter-subject variability in the pharmacokinetics of anti-TB drugs, further complicated by the recent increased dosing regimen of rifampicin strategies, calling for a patient-specific methodology. In this context, therapeutic drug monitoring (TDM), which allows personalized drug dosing based on blood drug concentrations, may be a legitimate solution to address treatment failure. This review focuses on rifampicin, a critical anti-TB drug, and examines its suitability for TDM and the socio-economic factors that may influence the implementation of TDM in clinical practice in resource-limited settings, illustrated by Tanzania, thereby contributing to the advancement of personalized TB treatment.

Pharmacology of emerging drugs for the treatment of multi-drug resistant tuberculosis

Mycobacterium tuberculosis (TB) remains the leading cause of infection-related mortality worldwide. Drug resistance, need for multiple antimycobacterial agents, prolonged treatment courses, and medication-related side effects are complicating factors to TB cure. The introduction of treatment regimens containing the novel agents bedaquiline, pretomanid, and linezolid, with or without moxifloxacin (BPaL-M or BPaL, respectively) have substantially reduced TB-related morbidity and mortality and are associated with favorable rates of treatment completion and cure. This review summarizes key information on the pharmacology and treatment principles for moxifloxacin, bedaquiline, delamanid, pretomanid, linezolid, and tedizolid in the treatment of multi-drug resistant TB, with recommendations provided to address and attenuate common adverse effects during treatment.

A CT-based radiomics analyses for differentiating drug‑resistant and drug-sensitive pulmonary tuberculosis

BACKGROUND

To explore the value of computed tomography based radiomics in the differential diagnosis of drug-sensitive and drug-resistant pulmonary tuberculosis.

METHODS

The clinical and computed tomography image data of 177 patients who were diagnosed with pulmonary tuberculosis through sputum culture and completed drug-susceptibility testing from April 2018 to December 2020 at the Second Hospital of Nanjing were retrospectively analyzed. Patients with drug-resistant pulmonary tuberculosis (n = 78) and drug-sensitive pulmonary tuberculosis (n = 99) were randomly divided into a training set (n = 124) and a validation set (n = 53) at a ratio of 7:3. Regions of interest were drawn to delineate the lesions and radiomics features were extracted from non-contrast computed tomography images. A radiomics signature based on the valuable radiomics features was constructed and a radiomics score was calculated. Demographic data, clinical symptoms, laboratory results and computed tomography imaging characteristics were evaluated to establish a clinical model. Combined with the Rad-score and clinical factors, a radiomics-clinical model nomogram was constructed.

RESULTS

Thirteen features were used to construct the radiomics signature. The radiomics signature showed good discrimination in the training set (area under the curve (AUC), 0.891; 95% confidence interval (CI), 0.832-0.951) and the validation set (AUC, 0.803; 95% CI, 0.674-0.932). In the clinical model, the AUC of the training set was 0.780(95% CI, 0.700-0.859), while the AUC of the validation set was 0.692 (95% CI, 0.546-0.839). The radiomics-clinical model showed good calibration and discrimination in the training set (AUC, 0.932;95% CI, 0.888-0.977) and the validation set (AUC, 0.841; 95% CI, 0.719-0.962).

CONCLUSIONS

Simple radiomics signature is of great value in differentiating drug-sensitive and drug-resistant pulmonary tuberculosis patients. The radiomics-clinical model nomogram showed good predictive, which may help clinicians formulate precise treatments.

Therapeutic drug monitoring in tuberculosis

PURPOSE

Therapeutic drug monitoring (TDM) is a standard clinical procedure that uses the pharmacokinetic and pharmacodynamic parameters of the drug in the body to determine the optimal dose. The pharmacokinetic variability of the drug(s) is a significant contributor to poor treatment outcomes, including the development of acquired drug resistance. TDM aids in dose optimization and improves outcomes while lessening drug toxicity. TDM is used to manage patients with tuberculosis (TB) who exhibit a slow response to therapy, despite good compliance and drug-susceptible organisms. Additional indications include patients at risk of malabsorption or delayed absorption of TB drugs and patients with drug-drug interaction and drug toxicity, which confirm compliance with therapy. TDM usually requires two blood samples: the 2 h and the 6 h post-dose. This narrative review will discuss the pharmacokinetics and pharmacodynamics of TB drugs, determinants of poor response to therapy, indications of TDM, methods of performing TDM, and its interpretations.

METHODS

This is a narrative review. We searched PubMed, Embase, and the CINAHL from inception to April 2024. We used the following search terms: tuberculosis, therapeutic drug monitoring, anti-TB drugs, pharmacokinetics, pharmacodynamics, limited sample strategies, diabetes and TB, HIV and TB, and multidrug-resistant TB. All types of articles were selected.

RESULTS

TDM is beneficial in managing TB, especially in patients with slow responses, drug-resistance TB, recurrent TB, and comorbidities such as diabetes mellitus and human immunodeficiency virus infection.

CONCLUSION

TDM is beneficial for improving outcomes, reducing the risk of acquired drug resistance, and avoiding side effects.

Pulmonary tuberculosis in non-HIV adults: an evergreen old-fashioned disease in high-income countries. A narrative review

INTRODUCTION

Tuberculosis (TB), an infective air-borne disease with worldwide non-homogeneous distribution, remains a top cause of morbidity and mortality. TB control is linked to early diagnosis and proper treatment of contagious TB cases and infected subjects at high risk of developing TB.

AREAS COVERED

A narrative review of pulmonary TB in non-HIV adults with reference to high-income countries. Modern medicine offers several advancements in diagnostics and therapeutics of TB, but they often remain to be extensively implemented in real life. In high-income countries TB is now relatively uncommon, but it remains a health and socio-economic burden that should not be underestimated.

EXPERT OPINION

Pulmonologists should maintain expertise toward TB for several reasons. First, the lung is the most common and the infectious moiety of TB. Second, TB remains a global issue due to common travels of western people and migrations from areas with high incidence of TB. Third, as TB has heterogenous clinics, its prompt diagnosis may be difficult. Fourth, TB is a curable disease, but its management is complex and predisposes to poor adherence with failures/relapses and selection of drug-resistant strains.

Mortality Rates after Tuberculosis Treatment, Georgia, USA, 2008-2019

Limited data exist on mortality rates after tuberculosis (TB) treatment in the United States. We analyzed mortality rates for all adults in Georgia, USA, who had a TB diagnosis and finished treatment during January 1, 2008-December 31, 2019. We obtained posttreatment mortality rate data from the National Death Index and calculated standardized mortality ratios (SMRs) for TB treatment survivors and the general Georgia population. Among 3,182 TB treatment survivors, 233 (7.3%) had died as of December 31, 2019. The overall TB cohort age- and sex-adjusted SMR was 0.89 (95% CI 0.73-1.05). The SMR among US-born TB treatment survivors was 1.56 (95% CI 1.36-1.77). In the TB cohort, US-born status, HIV co-infection, excess alcohol use, diabetes mellitus, and end-stage renal disease were associated with increased risk for death after TB treatment. TB treatment survivors could benefit from improved linkage to primary and HIV comprehensive care to prevent posttreatment death.

Efficacy of macozinone in mice with genetically diverse susceptibility to Mycobacterium tuberculosis infection

Host heterogeneity in pulmonary tuberculosis leads to varied responses to infection and drug treatment. The present portfolio of anti-TB drugs needs to be boosted with new drugs and drug regimens. Macozinone, a clinical-stage molecule targeting the essential enzyme, DprE1, represents an attractive option. Mice (I/St, B6, (AKRxI/St)F1, B6.I-100 and B6.I-139) genetically diverse susceptibility to Mycobacterium tuberculosis (Mtb) H37Rv infection were subjected to aerosol- or intravenous infection to determine the efficacy of macozinone (MCZ). They were treated with macozinone or reference drugs (isoniazid, rifampicin). Lung and spleen bacterial burdens were measured at four and eight weeks post-infection. Lung histology was evaluated at four weeks of treatment. Treatment with macozinone resulted in a statistically significant reduction in the bacterial load in the lungs and spleen as early as four weeks after treatment initiation in mice susceptible or resistant to Mtb infection. In the TB hypoxic granuloma model, macozinone was more potent than rifampicin in reducing the CFU counts. However, histopathological analysis revealed significant lung changes in I/St mice after eight weeks of treatment initiation. Macozinone demonstrated efficacy to varying degrees across all mouse models of Mtb infection used. These results should facilitate its further development and potential introduction into clinical practice.

Readability of Patient-Facing Information of Antibiotics Used in the WHO Short 6-Month and 9-Month All Oral Treatment for Drug-Resistant Tuberculosis

OBJECTIVES

Readability of patient-facing information of oral antibiotics detailed in the WHO all oral short (6 months, 9 months) has not been described to date. The aim of this study was therefore to examine (i) how readable patient-facing TB antibiotic information is compared to readability reference standards and (ii) if there are differences in readability between high-incidence countries versus low-incidence countries.

METHODS

Ten antibiotics, including bedaquiline, clofazimine, ethambutol, ethionamide, isoniazid, levofloxacin, linezolid, moxifloxacin, pretomanid, pyrazinamide, were investigated. TB antibiotic information sources were examined, consisting of 85 Patient Information Leaflets (PILs) and 40 antibiotic web resouces. Of these 85 PILs, 72 were taken from the National Medicines Regulator from six countries (3 TB high-incidence [Rwanda, Malaysia, South Africa] + 3 TB low-incidence [UK, Ireland, Malta] countries). Readability data was grouped into three categories, including (i) high TB-incidence countries (n = 33 information sources), (ii) low TB-incidence countries (n = 39 information sources) and (iii) web information (n = 53). Readability was calculated using Readable software, to obtain four readability scores [(i) Flesch Reading Ease (FRE), (ii) Flesch-Kincaid Grade Level (FKGL), (iii) Gunning Fog Index and (iv) SMOG Index], as well as two text metrics [words/sentence, syllables/word].

RESULTS

Mean readability scores of patient-facing TB antibiotic information for FRE and FKGL, were 47.4 ± 12.6 (sd) (target ≥ 60) and 9.2 ± 2.0 (target ≤ 8.0), respectively. There was no significant difference in readability between low incidence countries and web resources, but there was significantly poorer readability associated with PILs from high incidence countries versus low incidence countries (FRE; p = 0.0056: FKGL; p = 0.0095).

CONCLUSIONS

Readability of TB antibiotic PILs is poor. Improving readability of PILs should be an important objective when preparing patient-facing written materials, thereby improving patient health/treatment literacy.

Drug-resistant tuberculosis: a persistent global health concern

Drug-resistant tuberculosis (TB) is estimated to cause 13% of all antimicrobial resistance-attributable deaths worldwide and is driven by both ongoing resistance acquisition and person-to-person transmission. Poor outcomes are exacerbated by late diagnosis and inadequate access to effective treatment. Advances in rapid molecular testing have recently improved the diagnosis of TB and drug resistance. Next-generation sequencing of Mycobacterium tuberculosis has increased our understanding of genetic resistance mechanisms and can now detect mutations associated with resistance phenotypes. All-oral, shorter drug regimens that can achieve high cure rates of drug-resistant TB within 6-9 months are now available and recommended but have yet to be scaled to global clinical use. Promising regimens for the prevention of drug-resistant TB among high-risk contacts are supported by early clinical trial data but final results are pending. A person-centred approach is crucial in managing drug-resistant TB to reduce the risk of poor treatment outcomes, side effects, stigma and mental health burden associated with the diagnosis. In this Review, we describe current surveillance of drug-resistant TB and the causes, risk factors and determinants of drug resistance as well as the stigma and mental health considerations associated with it. We discuss recent advances in diagnostics and drug-susceptibility testing and outline the progress in developing better treatment and preventive therapies.

Disseminated MDR-TB missed in a patient treated with TNF inhibitor

A previously healthy man developed pulmonary symptoms 2 weeks after starting treatment with a tumour necrosis factor (TNF) inhibitor. A negative interferon-gamma release assay (IGRA) test was obtained prior to TNF inhibitor exposure, without consideration of the fact that the patient was already immunosuppressed and had a previous positive IGRA test 17 months earlier. The patient was treated for pneumonia twice but did not achieve remission. His physical health progressively deteriorated over the following months. Malignancy was suspected but not found. Eight months after the onset of symptoms, Mycobacterium tuberculosis was found in samples from mediastinal lymph nodes, and the patient was diagnosed with multidrug-resistant tuberculosis (MDR-TB).This case illustrates the diagnostic challenge of TB, the need to raise awareness of the increased risk of TB in patients treated with TNF inhibitors and the need to increase knowledge regarding the effect of immunosuppressive agents on IGRA tests.

Diagnosis, prevention and risk-management of drug-induced liver injury due to medications used to treat mycobacterium tuberculosis

INTRODUCTION

Many of the first line medications for the treatment of active and latent M. tuberculosis are hepatoxic and cause a spectrum of anti-tuberculosis drug induced liver injury (ATLI), including acute liver failure (ALF). Despite advances in recognition of and prevention of ATLI, isoniazid remains one of the leading causes of DILI as well as drug-induced ALF.

AREAS COVERED

A literature search of the incidence, risk factors, current societal guidelines, monitoring, and prophylactic medication usage in ATLI was performed using PubMed and institutional websites. Relevant articles from 1972 to 2024 were included in this review.

EXPERT OPINION

Current societal guidelines regarding ATLI monitoring are mixed, but many recommend liver enzyme testing of high-risk populations. We recommend liver test monitoring for all patients on multi-drug therapy as well as those on isoniazid therapy. Precision medicine practices, such as N-acetyltransferase-2 polymorphism genotyping, are thought to be beneficial in reducing the incidence of ATLI in high-risk populations. However, broader implementation is currently cost prohibitive. Hepatoprotective drugs are not currently recommended, although we do recognize their potential. In patients who develop ATLI but require ongoing anti-TB treatment, strategies to restart the same or less hepatotoxic regimens are currently being followed.

Breaking barriers: The potential of nanosystems in antituberculosis therapy

Tuberculosis (TB), caused by Mycobacterium tuberculosis, continues to pose a significant threat to global health. The resilience of TB is amplified by a myriad of physical, biological, and biopharmaceutical barriers that challenge conventional therapeutic approaches. This review navigates the intricate landscape of TB treatment, from the stealth of latent infections and the strength of granuloma formations to the daunting specters of drug resistance and altered gene expression. Amidst these challenges, traditional therapies often fail, contending with inconsistent bioavailability, prolonged treatment regimens, and socioeconomic burdens. Nanoscale Drug Delivery Systems (NDDSs) emerge as a promising beacon, ready to overcome these barriers, offering better drug targeting and improved patient adherence. Through a critical approach, we evaluate a spectrum of nanosystems and their efficacy against MTB both in vitro and in vivo. This review advocates for the intensification of research in NDDSs, heralding their potential to reshape the contours of global TB treatment strategies.

Prevalence and patterns of drug-resistant Mycobacterium tuberculosis in newly diagnosed patients in China: A systematic review and meta-analysis

BACKGROUND

Tuberculosis (TB), one of the deadliest infectious diseases globally, is increasingly exacerbated in China by the emergence of resistant Mycobacterium tuberculosis (MTB) strains. Drug-resistant TB, including mono-drug-resistant TB, multidrug-resistant TB (MDR-TB), and extensively drug-resistant TB (XDR-TB), presents significant public health challenges.

METHODS

We conducted a systematic literature review from January 2010 to February 2024 using databases such as PubMed, Embase, Web of Science, and Google Scholar. Our focus was on empirical data related to drug resistance patterns in newly diagnosed TB cases. Non-empirical studies were excluded through meticulous filtering. For the meta-analysis, we used Review Manager (RevMan) 5.2 and assessed evidence quality using the Newcastle-Ottawa Scale (NOS).

RESULTS

Our search strategy identified 40 studies that met the inclusion criteria, encompassing a total sample size of 87,667 participants. Among new TB cases, the estimated prevalence of MDR-TB in China was 6.9% (95% CI: 5.6-8.1%). Prevalence rates for mono-drug resistance to first-line anti-TB medications were as follows: isoniazid at 18.2% (95% CI: 16.4-20.6%), rifampicin at 10.5% (95% CI: 8.6-12.8%), and ethambutol at 5.7% (95% CI: 4.1-7.3%). The prevalence of streptomycin resistance, a former first-line anti-TB drug, was 17.1% (95% CI: 14.6-19.1%). The prevalence of other types of mono-drug resistance was 15.2% (95% CI: 13.9-17.3%), and for XDR-TB, it was 0.9% (95% CI: 0.6-1.4%).

CONCLUSIONS

The high prevalence of drug-resistant TB in China poses a significant public health challenge. There is an urgent need for targeted interventions and continued surveillance to combat the spread of drug-resistant TB.

Recent advances in the treatment of tuberculosis

BACKGROUND

Tuberculosis (TB) is a global health challenge and one of the leading causes of death worldwide. In the last decade, the TB treatment landscape has dramatically changed. After long years of stagnation, new compounds entered the market (bedaquiline, delamanid, and pretomanid) and phase III clinical trials have shown promising results towards shortening duration of treatment for both drug-susceptible (Study 31/A5349, TRUNCATE-TB, and SHINE) and drug-resistant TB (STREAM, NiX-TB, ZeNix, and TB-PRACTECAL). Dose optimization of rifamycins and repurposed drugs has also brought hopes of further development of safe and effective regimens. Consequently, international and WHO clinical guidelines have been updated multiple times in the last years to keep pace with these advances.

OBJECTIVES

This narrative review aims to summarize the state-of-the-art on treatment of drug-susceptible and drug-resistant TB, as well as recent trial results and an overview of ongoing clinical trials.

SOURCES

A non-systematic literature review was conducted in PubMed and MEDLINE, focusing on the treatment of TB. Ongoing clinical trials were listed according to the authors' knowledge and completed consulting clinicaltrials.gov and other publicly available websites (www.resisttb.org/clinical-trials-progress-report, www.newtbdrugs.org/pipeline/trials).

CONTENT

This review summarizes the recent, major changes in the landscape for drug-susceptible and drug-resistant treatment, with a specific focus on their potential impact on patient outcomes and programmatic TB management. Moreover, insights in host-directed therapies, and advances in pharmacokinetics and pharmacogenomics are discussed. A thorough outline of ongoing therapeutic clinical trials is presented, highlighting different approaches and goals in current TB clinical research.

IMPLICATIONS

Future research should be directed to individualize regimens and protect these recent breakthroughs by preventing and identifying the selection of drug resistance and providing widespread, affordable, patient-centred access to new treatment options for all people affected by TB.

Multidrug-resistant tuberculosis in children: A practical update on epidemiology, diagnosis, treatment and prevention

Pediatric multidrug-resistant tuberculosis (MDR-TB) remains a significant global problem, and there are numerous barriers preventing children with MDR-TB from being identified, confirmed with microbiologic tests, and treated with a safe, practical, and effective regimen. However, several recent advances in diagnostics and treatment regimens have the promise to improve outcomes for children with MDR-TB. We introduce this review with two cases that exemplify both the challenges in management of MDR-TB in children, but also the potential to achieve a positive outcome. More than 30,000 cases of MDR-TB per year are believed to occur in children but less than 5% are confirmed microbiologically, contributing to poorer outcomes and excess mortality. Rapid molecular-based testing that provides information on rifampin susceptibility is increasingly globally available and recommended for all children suspected of TB disease--but remains limited by challenges obtaining appropriate samples and the paucibacillary nature of most pediatric TB. More complex assays allowing better characterization of drug-resistant isolates are emerging. For children diagnosed with MDR-TB, treatment regimens have traditionally been long and utilize multiple drugs associated with significant side effects, particularly injectable agents. Several new or repurposed drugs including bedaquiline, delamanid, clofazimine and linezolid now allow most treatment regimens to be shorter and all-oral. Yet data to support short, all-oral, novel regimens for young children containing pretomanid remain insufficient at present, and there is a compelling need to conduct pediatric trials of promising therapeutics and MDR-TB treatment regimens.

Role of therapeutic drug monitoring in the treatment of multi-drug resistant tuberculosis

Tuberculosis (TB) is a leading cause of mortality worldwide, and resistance to anti-tuberculosis drugs is a challenge to effective treatment. Multi-drug resistant TB (MDR-TB) can be difficult to treat, requiring long durations of therapy and the use of second line drugs, increasing a patient's risk for toxicities and treatment failure. Given the challenges treating MDR-TB, clinicians can improve the likelihood of successful outcomes by utilizing therapeutic drug monitoring (TDM). TDM is a clinical technique that utilizes measured drug concentrations from the patient to adjust therapy, increasing likelihood of therapeutic drug concentrations while minimizing the risk of toxic drug concentrations. This review paper provides an overview of the TDM process, pharmacokinetic parameters for MDR-TB drugs, and recommendations for dose adjustments following TDM.

Effect of Cost-Exemption Policy on Treatment Interruption in Patients With Newly Diagnosed Pulmonary Tuberculosis in South Korea

BACKGROUND

In 2021, South Korea had the highest incidence rate (49 per 100 000 population) and the third highest mortality rate (3.8 per 100 000 population) due to pulmonary tuberculosis (TB) among Organization for Economic Co-operation and Development countries. Notably, premature interruption of TB treatment interferes with TB control efforts. Therefore, we examined the effect of the co-payment waiver on treatment interruption and mortality among patients with pulmonary TB in South Korea.

METHODS

Patients who had newly treated TB in South Korea from 2013 to 2019 were selected from the nationwide data of the entire Korean National Health Insurance Service (NHIS) population. The effects of policy implementation on treatment adherence and mortality rates depending on treatment interruption history were evaluated.

RESULTS

In total, 73 116 and 1673 patients with drug-susceptible (DS) and multidrug-resistant (MDR) pulmonary TB, respectively, were included in the final study population. After implementing the cost-exemption policy, the treatment interruption rate tended to decrease in the continuation phase in the DS-TB group (slope change: -0.097, P=.011). However, it increased in the intensive phase in the MDR-TB group (slope change: 0.733, P=.001). MDR-TB patients were likely to experience an interruption of TB treatment (adjusted odds ratio [aOR], 6.04; 95% CI, 5.43-6.71), and treatment interruption history was a significant risk factor for 1-year and overall mortality rates (adjusted hazard ratios [aHRs]: 2.01, 95% CI, 1.86-2.18 and 1.77, 95% CI, 1.70-1.84, respectively) in the DS-TB group.

CONCLUSION

Implementing the cost-exemption policy effectively reduced the treatment interruption rate among patients with DS pulmonary TB.

Two Cases of Testicular Tuberculosis and Review of the Recent Literature

In this review, two cases of testicular tuberculosis (TB) are presented, and another 58 cases published in PubMed between January 1, 2012, and July 31, 2023, are reviewed. Testicular TB remains a disease mainly of the developing world, with one notable exception - the infections caused as a result of Bacillus Calmette-Guérin infusion immunotherapy for bladder cancer. Its clinical course is subacute; however, it might get disseminated and become life-threatening; therefore, prompt diagnosis is very important. The diagnosis can be quite challenging, and testicular tissue is the sample with the highest diagnostic yield, either for microbiological or histopathological diagnosis. On the other hand, its treatment follows the standard guidelines for TB treatment; however, the avoidance of an unnecessary orchiectomy is important.

Identification of Axinellamines A and B as Anti-Tubercular Agents

Tuberculosis remains a significant global health pandemic. There is an urgent need for new anti-tubercular agents to combat the rising incidence of drug resistance and to offer effective and additive therapeutic options. High-throughput screening of a subset of the NatureBank marine fraction library (n = 2000) identified a sample derived from an Australian marine sponge belonging to the order Haplosclerida that displayed promising anti-mycobacterial activity. Bioassay-guided fractionation of the organic extract from this Haplosclerida sponge led to the purification of previously identified antimicrobial pyrrole alkaloids, axinellamines A (1) and B (2). The axinellamine compounds were found to have a 90% minimum inhibitory concentration (MIC90) of 18 µM and 15 µM, respectively. The removal of protein and complex carbon sources reduced the MIC90 of 1 and 2 to 0.6 and 0.8 µM, respectively. The axinellamines were not toxic to mammalian cells at 25 µM and significantly reduced the intracellular bacterial load by >5-fold. These data demonstrate that axinellamines A and B are effective anti-tubercular agents and promising targets for future medicinal chemistry efforts.

Microfluidics produced ATRA-loaded PLGA NPs reduced tuberculosis burden in alveolar epithelial cells and enabled high delivered dose under simulated human breathing pattern in 3D printed head models

Tuberculosis, caused by Mycobacterium tuberculosis (Mtb), is second only to COVID-19 as the top infectious disease killer worldwide. Multi-drug resistant TB (MDR-TB) may arise because of poor patient adherence to medications due to lengthy treatment duration and side effects. Delivering novel host directed therapies (HDT), like all trans retinoic acid (ATRA) may help to improve drug regimens and reduce the incidence of MDR-TB. Local delivery of ATRA to the site of infection leads to higher bioavailability and reduced systemic side effects. ATRA is poorly soluble in water and has a short half-life in plasma. Therefore, it requires a formulation step before it can be administered in vivo. ATRA loaded PLGA nanoparticles suitable for nebulization were manufactured and optimized using a scalable nanomanufacturing microfluidics (MF) mixing approach (MF-ATRA-PLGA NPs). MF-ATRA-PLGA NPs demonstrated a dose dependent inhibition of Mtb growth in TB-infected A549 alveolar epithelial cell model while preserving cell viability. The MF-ATRA-PLGA NPs were nebulized with the Aerogen Solo vibrating mesh nebulizer, with aerosol droplet size characterized using laser diffraction and the estimated delivered dose was determined. The volume median diameter (VMD) of the MF-ATRA-PLGA NPs was 3.00 ± 0.18 μm. The inhaled dose delivered in adult and paediatric 3D printed head models under a simulated normal adult and paediatric breathing pattern was found to be 47.05 ± 3 % and 20.15 ± 3.46 % respectively. These aerosol characteristics of MF-ATRA-PLGA NPs supports its suitability for delivery to the lungs via inhalation. The data generated on the efficacy of an inhalable, scalable and regulatory friendly ATRA-PLGA NPs formulation provides a foundation on which further pre-clinical testing can be built. Overall, the results of this project are promising for future research into ATRA loaded NPs formulations as inhaled host directed therapies for TB.

FBXO32-mediated degradation of PTEN promotes lung adenocarcinoma progression

FBXO32, a member of the F-box protein family, is known to play both oncogenic and tumor-suppressive roles in different cancers. However, the functions and the molecular mechanisms regulated by FBXO32 in lung adenocarcinoma (LUAD) remain unclear. Here, we report that FBXO32 is overexpressed in LUAD compared with normal lung tissues, and high expression of FBXO32 correlates with poor prognosis in LUAD patients. Firstly, we observed with a series of functional experiments that FBXO32 alters the cell cycle and promotes the invasion and metastasis of LUAD cells. We further corroborate our findings using in vivo mouse models of metastasis and confirmed that FBXO32 positively regulates LUAD tumor metastasis. Using a proteomic-based approach combined with computational analyses, we found a positive correlation between FBXO32 and the PI3K/AKT/mTOR pathway, and identified PTEN as a FBXO32 interactor. More important, FBXO32 binds PTEN via its C-terminal substrate binding domain and we also validated PTEN as a bona fide FBXO32 substrate. Finally, we demonstrated that FBXO32 promotes EMT and regulates the cell cycle by targeting PTEN for proteasomal-dependent degradation. In summary, our study highlights the role of FBXO32 in promoting the PI3K/AKT/mTOR pathway via PTEN degradation, thereby fostering lung adenocarcinoma progression.

The great imitator: Tuberculosis with lymphadenopathy and splenomegaly

Tuberculosis (TB) is a leading infectious killer worldwide. Over two-thirds of new TB diagnoses in the United States occur among first-generation immigrants, especially within a year of migration. Hodgkin lymphoma (HL) accounts for a minority of lymphoma cases but presents similarly to disseminated or extrapulmonary TB. Clinical overlap between TB and HL increases patient risk of misdiagnosis. Concomitant presentation of both diseases is not uncommon but infrequently reported. We present a case of isoniazid-resistant TB with progressively worsening lymphadenopathy and splenomegaly despite appropriate TB treatment. The patient was diagnosed with HL following PET/CT and axillary lymph node biopsy.

Proteomics study the potential targets for Rifampicin-resistant spinal tuberculosis

Introduction: The escalating global surge in Rifampicin-resistant strains poses a formidable challenge to the worldwide campaign against tuberculosis (TB), particularly in developing countries. The frequent reports of suboptimal treatment outcomes, complications, and the absence of definitive treatment guidelines for Rifampicin-resistant spinal TB (DSTB) contribute significantly to the obstacles in its effective management. Consequently, there is an urgent need for innovative and efficacious drugs to address Rifampicin-resistant spinal tuberculosis, minimizing the duration of therapy sessions. This study aims to investigate potential targets for DSTB through comprehensive proteomic and pharmaco-transcriptomic analyses. Methods: Mass spectrometry-based proteomics analysis was employed to validate potential DSTB-related targets. PPI analysis confirmed by Immunohistochemistry (IHC) and Western blot analysis. Results: The proteomics analysis revealed 373 differentially expressed proteins (DEPs), with 137 upregulated and 236 downregulated proteins. Subsequent Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses delved into the DSTB-related pathways associated with these DEPs. In the context of network pharmacology analysis, five key targets-human leukocyte antigen A chain (HLAA), human leukocyte antigen C chain (HLA-C), HLA Class II Histocompatibility Antigen, DRB1 Beta Chain (HLA-DRB1), metalloproteinase 9 (MMP9), and Phospholipase C-like 1 (PLCL1)-were identified as pivotal players in pathways such as "Antigen processing and presentation" and "Phagosome," which are crucially enriched in DSTB. Moreover, pharmaco-transcriptomic analysis can confirm that 58 drug compounds can regulate the expression of the key targets. Discussion: This research confirms the presence of protein alterations during the Rifampicin-resistant process in DSTB patients, offering novel insights into the molecular mechanisms underpinning DSTB. The findings suggest a promising avenue for the development of targeted drugs to enhance the management of Rifampicin-resistant spinal tuberculosis.

A pregnant woman with pre-XDR PTB giving birth to a healthy newborn: A case report

We reported a late-pregnancy woman with pre-XDR PTB who had not received regular anti-tuberculosis treatment prior to delivery. Despite this, she successfully delivered a premature baby who exhibited normal growth and development, and subsequently completed her anti-tuberculosis treatment. This report suggests that delayed treatment for pre-XDR TB during late pregnancy does not necessarily increase the risk of treatment failure for the mother or the risk of neonatal tuberculosis.

Tuberculosis treatment monitoring tests during routine practice: study design guidance

SCOPE

The current tools for tuberculosis (TB) treatment monitoring, smear microscopy and culture, cannot accurately predict poor treatment outcomes. Research into new TB treatment monitoring tools (TMTs) is growing, but data are unreliable. In this article, we aim to provide guidance for studies investigating and evaluating TB TMT for use during routine clinical care. Here, a TB TMT would guide treatment during the course of therapy, rather than testing for a cure at the regimen's end. This article does not cover the use of TB TMTs as surrogate endpoints in the clinical trial context.

METHODS

Guidelines were initially informed by experiences during a systematic review of TB TMTs. Subsequently, a small content expert group was consulted for feedback on initial recommendations. After revision, feedback from substantive experts across sectors was sought.

QUESTIONS ADDRESSED BY THE GUIDELINE AND RECOMMENDATIONS

The proposed considerations and recommendations for studies evaluating TB TMTs for use during the treatment in routine clinical care fall into eight domains. We provide specific recommendations regarding study design and recruitment, outcome definitions, reference standards, participant follow-up, clinical setting, study population, treatment regimen reporting, and index tests and data presentation. Overall, TB TMTs should be evaluated in a manner similar to diagnostic tests, but TB TMT accuracy must be assessed at multiple timepoints throughout the treatment course, and TB TMTs should be evaluated in study populations who have already received a diagnosis of TB. Study design and outcome definitions must be aligned with the developmental phase of the TB TMT under evaluation. There is no reference standard for TB treatment response, so different reference standards and comparator tests have been proposed, the selection of which will vary depending on the developmental phase of the TMT under assessment. The use of comparator tests can assist in generating evidence. Clarity is required when reporting of timepoints, TMT read-outs, and analysis results. Implementing these recommendations will lead to higher quality TB TMT studies that will allow data to be meaningfully compared, thereby facilitating the development of novel tools to guide individual TB therapy and improve treatment outcomes.

Oral linezolid compared with benzathine penicillin G for treatment of early syphilis in adults (Trep-AB Study) in Spain: a prospective, open-label, non-inferiority, randomised controlled trial

BACKGROUND

Management of syphilis, a sexually transmitted infection (STI) with increasing incidence, is challenged by drug shortages, scarcity of randomised trial data, an absence of non-penicillin alternatives for pregnant women with penicillin allergy (other than desensitisation), extended parenteral administration for neurosyphilis and congenital syphilis, and macrolide resistance. Linezolid was shown to be active against Treponema pallidum, the causative agent of syphilis, in vitro and in the rabbit model. We aimed to assess the efficacy of linezolid for treating early syphilis in adults compared with the standard of care benzathine penicillin G (BPG).

METHODS

We did a multicentre, open-label, non-inferiority, randomised controlled trial to assess the efficacy of linezolid for treating early syphilis compared with BPG. We recruited participants with serological or molecular confirmation of syphilis (either primary, secondary, or early latent) at one STI unit in a public hospital and two STI community clinics in Catalonia (Spain). Participants were randomly allocated in a 1:1 ratio using a computer-generated block randomisation list with six participants per block, to receive either oral linezolid (600 mg once per day for 5 days) or intramuscular BPG (single dose of 2·4 million international units) and were assessed for signs and symptoms (once per week until week 6 and at week 12, week 24, and week 48) and reagin titres of non-treponemal antibodies (week 12, week 24, and week 48). The primary endpoint was treatment response, assessed using a composite endpoint that included clinical response, serological response, and absence of relapse. Clinical response was assessed at 2 weeks for primary syphilis and at 6 weeks for secondary syphilis following treatment initiation. Serological cure was defined as a four-fold decline in rapid plasma reagin titre or seroreversion at any of the 12-week, 24-week, or 48-week timepoints. The absence of relapse was defined as the presence of different molecular sequence types of T pallidum in recurrent syphilis. Non-inferiority was shown if the lower limit of the two-sided 95% CI for the difference in rates of treatment response was higher than -10%. The primary analysis was done in the per-protocol population. The trial is registered at ClinicalTrials.gov (NCT05069974) and was stopped for futility after interim analysis.

FINDINGS

Between Oct 20, 2021, and Sept 15, 2022, 62 patients were assessed for eligibility, and 59 were randomly assigned to linezolid (n=29) or BPG (n=30). In the per-protocol population, after 48 weeks' follow-up, 19 (70%) of 27 participants (95% CI 49·8 to 86·2) in the linezolid group had responded to treatment and 28 (100%) of 28 participants (87·7 to 100·0) in the BPG group (treatment difference -29·6, 95% CI -50·5 to -8·8), which did not meet the non-inferiority criterion. The number of drug-related adverse events (all mild or moderate) was similar in both treatment groups (five [17%] of 29, 95% CI 5·8 to 35·8 in the linezolid group vs five [17%] of 30, 5·6 to 34·7, in the BPG group). No serious adverse events were reported during follow-up.

INTERPRETATION

The efficacy of linezolid at a daily dose of 600 mg for 5 days did not meet the non-inferiority criteria compared with BPG and, as a result, this treatment regimen should not be used to treat patients with early syphilis.

FUNDING

European Research Council and Fondo de Investigaciones Sanitarias.

Estimation of country-specific tuberculosis resistance antibiograms using pathogen genomics and machine learning

BACKGROUND

Global tuberculosis (TB) drug resistance (DR) surveillance focuses on rifampicin. We examined the potential of public and surveillance Mycobacterium tuberculosis (Mtb) whole-genome sequencing (WGS) data, to generate expanded country-level resistance prevalence estimates (antibiograms) using in silico resistance prediction.

METHODS

We curated and quality-controlled Mtb WGS data. We used a validated random forest model to predict phenotypic resistance to 12 drugs and bias-corrected for model performance, outbreak sampling and rifampicin resistance oversampling. Validation leveraged a national DR survey conducted in South Africa.

RESULTS

Mtb isolates from 29 countries (n=19 149) met sequence quality criteria. Global marginal genotypic resistance among mono-resistant TB estimates overlapped with the South African DR survey, except for isoniazid, ethionamide and second-line injectables, which were underestimated (n=3134). Among multidrug resistant (MDR) TB (n=268), estimates overlapped for the fluoroquinolones but overestimated other drugs. Globally pooled mono-resistance to isoniazid was 10.9% (95% CI: 10.2-11.7%, n=14 012). Mono-levofloxacin resistance rates were highest in South Asia (Pakistan 3.4% (0.1-11%), n=111 and India 2.8% (0.08-9.4%), n=114). Given the recent interest in drugs enhancing ethionamide activity and their expected activity against isolates with resistance discordance between isoniazid and ethionamide, we measured this rate and found it to be high at 74.4% (IQR: 64.5-79.7%) of isoniazid-resistant isolates predicted to be ethionamide susceptible. The global susceptibility rate to pyrazinamide and levofloxacin among MDR was 15.1% (95% CI: 10.2-19.9%, n=3964).

CONCLUSIONS

This is the first attempt at global Mtb antibiogram estimation. DR prevalence in Mtb can be reliably estimated using public WGS and phenotypic resistance prediction for key antibiotics, but public WGS data demonstrates oversampling of isolates with higher resistance levels than MDR. Nevertheless, our results raise concerns about the empiric use of short-course fluoroquinolone regimens for drug-susceptible TB in South Asia and indicate underutilisation of ethionamide in MDR treatment.

Multidrug-resistant tuberculosis

Tuberculosis (TB) remains the foremost cause of death by an infectious disease globally. Multidrug-resistant or rifampicin-resistant TB (MDR/RR-TB; resistance to rifampicin and isoniazid, or rifampicin alone) is a burgeoning public health challenge in several parts of the world, and especially Eastern Europe, Russia, Asia and sub-Saharan Africa. Pre-extensively drug-resistant TB (pre-XDR-TB) refers to MDR/RR-TB that is also resistant to a fluoroquinolone, and extensively drug-resistant TB (XDR-TB) isolates are additionally resistant to other key drugs such as bedaquiline and/or linezolid. Collectively, these subgroups are referred to as drug-resistant TB (DR-TB). All forms of DR-TB can be as transmissible as rifampicin-susceptible TB; however, it is more difficult to diagnose, is associated with higher mortality and morbidity, and higher rates of post-TB lung damage. The various forms of DR-TB often consume >50% of national TB budgets despite comprising <5-10% of the total TB case-load. The past decade has seen a dramatic change in the DR-TB treatment landscape with the introduction of new diagnostics and therapeutic agents. However, there is limited guidance on understanding and managing various aspects of this complex entity, including the pathogenesis, transmission, diagnosis, management and prevention of MDR-TB and XDR-TB, especially at the primary care physician level.

Mycobacterium tuberculosis Lineage Distribution Using Whole-Genome Sequencing and Bedaquiline, Clofazimine, and Linezolid Phenotypic Profiles among Rifampicin-Resistant Isolates from West Java, Indonesia

Tuberculosis (TB) is caused by Mycobacterium tuberculosis infection. Indonesia is ranked second in the world for TB cases. New anti-TB drugs from groups A and B, such as bedaquiline, clofazimine, and linezolid, have been shown to be effective in curing drug resistance in TB patients, and Indonesia is already using these drugs to treat patients. However, studies comparing the TB strain types with anti-TB resistance profiles are still relevant to understanding the prevalent strains in the country and their phenotypic characteristics. This study aimed to determine the association between the TB lineage distribution using whole-genome sequencing and bedaquiline, clofazimine, and linezolid phenotypic profile resistance among M. tuberculosisrifampicin-resistant isolates from West Java. M. tuberculosis isolates stock of the Department of Microbiology, Faculty of Medicine, Universitas Indonesia, was tested against bedaquiline, clofazimine, and linezolid using a mycobacteria growth indicator tube liquid culture. All isolates were tested for M. tuberculosis and rifampicin resistance using Xpert MTB/RIF. The DNA genome of M. tuberculosis was freshly extracted from a Löwenstein-Jensen medium culture and then sequenced. The isolates showed phenotypically resistance to bedaquiline, clofazimine, and linezolid at 5%, 0%, and 0%, respectively. We identified gene mutations on phenotypically bedaquiline-resistant strains (2/3), and other mutations also found in phenotypically drug-sensitive strains. Mykrobe analysis showed that most (88.33%) of the isolates could be classified as rifampicin-resistant TB. Using Mykrobe and TB-Profiler to determine the lineage distribution, the isolates were found to belong to lineage 4 (Euro-American; 48.33%), lineage 2 (East Asian/Beijing; 46.67%), and lineage 1 (Indo-Oceanic; 5%). This work underlines the requirement to increase the representation of genotype-phenotype TB data while also highlighting the importance and efficacy of WGS in predicting medication resistance and inferring disease transmission.

Updates in pulmonary drug-resistant tuberculosis pharmacotherapy: A focus on BPaL and BPaLM

Drug-resistant tuberculosis (TB) is a major public health concern and contributes to high morbidity and mortality. New evidence supports the use of shorter duration, all-oral regimens, which represent an encouraging treatment strategy for drug-resistant TB. As a result, the landscape of drug-resistant TB pharmacotherapy has drastically evolved regarding treatment principles and preferred agents. This narrative review focuses on the key updates of drug-resistant TB treatment, including the use of short-duration all-oral regimens, while calling attention to current gaps in knowledge that may be addressed in future observational studies.